As populations in the world's largest cities continue to grow, often at an exponential rate, public and private transportation systems are becoming increasingly burdened with increased ridership and transit stations are becoming increasingly congested, causing delays to transit users and increased costs to the transportation systems. The use of sophisticated communication devices presents an appealing approach for managing such overcrowding. Unfortunately, existing devices and approaches are insufficient to alleviate these problems. Accordingly, new systems, methods, and other techniques are needed.